%0 Journal Article
%4 sid.inpe.br/mtc-m21d/2022/11.22.11.47
%2 sid.inpe.br/mtc-m21d/2022/11.22.11.47.03
%@doi 10.3390/atmos13111836
%@issn 2073-4433
%T Intertropical Convergence Zone as the Possible Source Mechanism for Southward Propagating Medium-Scale Traveling Ionospheric Disturbances over South American Low-Latitude and Equatorial Region
%D 2022
%8 Nov
%9 journal article
%A Essien, Patrick,
%A Figueiredo, Cosme Alexandre Oliveira Barros,
%A Takahashi, Hisao,
%A Klutse, Nana Ama Browne,
%A Wrasse, Cristiano Max,
%A Afonso, João Maria de Sousa,
%A Quispe, David Pareja,
%A Lomotey, Solomon Otoo,
%A Ayorinde, Tunde Toyese,
%A Sobral, José Humberto Andrade,
%A Eghan, Moses Jojo,
%A Sackey, Samuel Sanko,
%A Silva, Diego Barros,
%A Bilibio, Anderson Vestena,
%A Nkrumah, Francis,
%A Quagraine, Kwesi Akumenyi,
%@affiliation University of Cape Coast
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation African Institute for Mathematical Sciences (AIMS)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation National Institute of Meteorology and Geophysics of Angola (INAMET)
%@affiliation Universidad Nacional Mayor de San Marcos (UNMSM)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation University of Cape Coast
%@affiliation University of Cape Coast
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation University of Cape Coast
%@affiliation University of Cape Coast
%@electronicmailaddress
%@electronicmailaddress anagetinga@hotmail.com
%@electronicmailaddress
%@electronicmailaddress nklutse@ug.edu.gh
%@electronicmailaddress cristiano.wrasse@inpe.br
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress lomoteys@gmail.com
%@electronicmailaddress toyetunde@gmail.com
%@electronicmailaddress jhasobral@yahoo.com.br
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress bar_diego@hotmail.com
%@electronicmailaddress andersonvestenabilibio05@gmail.com
%B Atmosphere
%V 13
%N 11
%P e1836
%K gravity waves, ionosphere, ITCZ, MSTIDs.
%X This paper presents the Intertropical Convergence Zone (ITCZ) as the possible source mechanism of the medium-scale traveling ionospheric disturbances (MSTIDs) propagating to the southeast direction over the South American region. Using the data collected by the GNSS dual-frequency receivers network from January 2014 to December 2019, detrended TEC maps were generated to identify and characterize 144 MSTIDs propagating southeastward over the South American low-latitude and equatorial region. We also used images from the Geostationary Operational Environmental Satellite (GOES) 13 and 16 in the infrared (IR) and water vapor (WV) channel, and reanalisys data from the National Centers for Environmental Prediction (NCEP) of the National Oceanic and Atmospheric Administration (NOAA) to study the daily features and seasonal migration of ITCZ. In the winter, when ITCZ migrates to the northern hemisphere around 1015° N, 20 MSTIDs propagated southeastward. During summer, when the ITCZ lies within the continent, around 05° S 80 MSTIDs were observed to propagate southeastward; in the equinoxes (spring and fall), 44 MSTIDs were observed. Again, the MSTIDs propagating southeastward showed a clear seasonality of their local time dependence; in summer, the MSTIDs occurred frequently in the evening hours, whereas those in winter occurred during the daytime. We also found for the first time that the day-to-day observation of ITCZ position and MSTIDs propagation directions were consistent. With regard to these new findings, we report that the MSTIDs propagating southeastward over the South American region are possibly induced by the atmospheric gravity waves, which are proposed as being generated by the ITCZ in the troposphere. The mean distribution of the horizontal wavelength, period, and phase velocity are 698 ± 124 km, 38 ± 8 min, and 299 ± 89 m s−1, respectively. For the first time, we were able to use MSTID propagation directions as a proxy to study the source region.
%@language en
%3 atmosphere-13-01836.pdf